The present invention relates to a packaged face seal and, more specifically, to a face seal cartridge assembly and a method of using same.
Many mechanical systems include a shaft rotatable within a bore. There is often a clearance between the shaft and the bore which allows oil or other fluid to cushion and lubricate the shaft/bore interface. It is desirable to keep the fluid within the clearance, so a face seal is generally used to prevent the fluid from escaping. In a face seal, a sealing member is attached to each of the shaft and the bore. The sealing member attached to the shaft rotates with the shaft and the shaft and bore sealing members contact each other to form a seal.
A protective structure is normally provided to keep the sealing members in place and maintain integrity of the seal. This structure may include o-rings, plates, sleeves, or any other suitable components and may be associated with the sealing members in a cartridge-style assembly before the sealing members are installed in the shaft/bore clearance area. An example of a seal cartridge for a face seal is disclosed in U.S. Pat. No. 6,322,079, issued Nov. 27, 2001 to John J. Mullaney, III (hereafter referenced as ""079).
The ""079 face seal cartridge requires numerous different components, resulting in spare parts and maintenance inefficiencies. In addition, the complicated and detailed shapes of the components make manufacturing defects and failures in service more likely. Finally, ""079 makes no provision for testing and adjusting the face seal cartridge before installation on the shaft and bore.
The present invention is directed to overcoming one or more of the problems as set forth above.
In a preferred embodiment of the present invention, a face seal cartridge is provided. The face seal cartridge includes first and second sealing members and first and second o-rings, and first and second cartridge walls and a cartridge bottom. The first sealing member has a first top side and a first bottom side. The second sealing member has a second top side and a second bottom side, and the second bottom side is adapted to contact the first bottom side to form a face seal. The cartridge bottom is located adjacent the first and second bottom sides, has a U-shaped cross-section, and partially surrounds the first and second sealing members. The first cartridge wall is located adjacent and partially surrounding the first sealing member, and contacts the cartridge bottom. The second cartridge wall is located adjacent and partially surrounding the second sealing member and the first cartridge wall. The first o-ring provides a fluid-tight connection between the first sealing member and the first cartridge wall. The second o-ring provides a fluid-tight connection between the second sealing member and the second cartridge wall.
In a preferred embodiment of the present invention, a sealed rotating assembly, including a first structure, a second structure, and a face seal cartridge as above is disclosed.
In a preferred embodiment of the present invention, a method of making and installing a face seal cartridge is disclosed. The method includes the steps of: providing a cartridge bottom having a U-shaped cross section; positioning a first sealing member, having a first top side and a first bottom side, around the cartridge bottom and within the U-shaped cross section; and positioning a second sealing member, having a second top side and a second bottom side, around the cartridge bottom and within the U-shaped cross section, the first and second sealing members bending such that the first and second bottom sides come into contact. The method also includes the steps of: positioning a first o-ring around the first sealing member in contact with the first top side, positioning a second o-ring around the second sealing member in contact with the second top side, positioning a first cartridge wall around the first o-ring and in contact with the cartridge bottom and the first o-ring, and positioning a second cartridge wall around the second o-ring and in contact with the second o-ring to form the face seal cartridge. The method also includes the steps of: placing the face seal cartridge at least partially within a clearance between two relatively rotatable structures, applying force to the face seal cartridge, and forcing the face seal cartridge into an interference fit with the two relatively rotatable structures.